The present invention relates to a catalyst for the synthesis of chlorine dioxide and to a method of making such a catalyst. The catalyst is preferably palladium, or palladium together with another platinum group metal (e.g., Pd+Pt), or palladium together with a Group IB metal (e.g., Pd+Au) deposited on a support consisting of a Group IA carbonate salt (e.g., K.sub.2 CO.sub.3) or a Group IIA carbonate salt (e.g., CaCO.sub.3) or a magnesium salt that can be converted to MgO or a support modified by Group IA carbonate salt (e.g., K.sub.2 CO.sub.3) or a Group IIA carbonate salt (e.g., CaCO.sub.3) or a magnesium salt that can be converted to MgO. The catalysts of the present invention has a slower rate of deactivation than catalysts previously used for this purpose.
In another aspect, the present invention concerns a method for generating chlorine dioxide from an aqueous solution of a precursor therefor and directing the resulting chlorine dioxide at the material to be disinfected.
Chlorine dioxide is known to act as a disinfecting or sterilizing agent for solutions and devices (e.g., contact lenses). Chlorine dioxide is generally produced from a solution of a chlorine dioxide precursor, such as sodium chlorite solutions, by contacting the solution with a catalyst (e.g., catalysts containing noble metals, as described for example in U.S. Pat. No. 5,008,096). However, known catalysts have the disadvantage of becoming greatly deactivated within a matter of days.